The idea is that identifying people infected with HIV and getting them in effective treatment as soon as possible not only prevents them from getting sick but almost eliminates the risk they'll pass the virus on to others.

Last summer a big study showed that people with HIV are 96 percent less likely to pass the virus on if they faithfully take antiviral medicine. Momentum behind treatment-as-prevention has grown since then.

This is a big change. For a long time in the world of HIV and AIDS, the conventional wisdom has been to delay treatment until people show signs of damage to their immune system. Partly this is because the drugs have side effects (although some are now easier to take), and partly because few people thought medical treatment itself could slow the spread of HIV.

"After many years of frustration, it is a transformational moment in the course of this epidemic," says Kevin Cranston, head of infectious disease control at the Massachusetts Department of Public Health. "Universal treatment can in fact result in an epidemic that looks to be petering out."

Massachusetts is one of the places where it's actually beginning to happen. There are so many people on treatment that new infections are dwindling — a tipping point after years of increases.

"We, unlike most states and frankly most cities in the country, are seeing a sharp decline in the number of new cases of HIV over the past decade," Cranston says. New infections have fallen by nearly half and deaths from AIDS are at an all-time low in Massachusetts.

"We're approaching a level where the rate of transmission does not sustain an epidemic," he says.

Preventing HIV infection requires not only treating almost everybody with the virus but getting them to take antiviral pills faithfully, so that blood levels of the virus are suppressed to levels undetectable with standard tests. In Massachusetts, indications are that more than 70 percent of people on treatment have undetectable virus — compared with a national rate of under 30 percent.

But even in Massachusetts, many people still don't know they have HIV or they wait too long to get tested. Nearly 1 in 3 new cases already has full-blown AIDS or is close to it.

"It's a tragedy if someone doesn't present for care until they have an AIDS diagnosis," Cranston says. It means they've been infected for years, and able to infect others.

It's true all over the country. Nearly a quarter-million Americans have HIV without knowing it. And many others who do know they're infected are not getting treated.

That's why there's a big push now to do what AIDS experts are calling "test and treat" — reach out to people who might be infected, get them tested, and if they're HIV-positive get them into treatment as soon as possible.

But AIDS researcher Rochelle Walensky at the Massachusetts General Hospital cautions against expecting too much. She says test-and-treat programs are never going to get 100 percent of people into effective, long-term treatment. But they should get as close as they can.

"If we could find everybody with HIV, link them to care, make sure they were getting treatment and doing well, we could make a huge dent in this epidemic," Walensky says. "Could we eradicate it? Perhaps ... but it'll take a long time."

The problem is, many of those not yet in treatment have other, more urgent priorities than getting tested for HIV — and then taking pills for it without fail for the rest of their lives.

Kenya Jackson is one of those HIV patients who have been very hard to keep in treatment. He's a 52-year-old Boston man with lots of problems. On top of his HIV infection, Jackson has kidney failure, hepatitis B and high blood pressure. He's also been homeless for years.

Jackson found out he had the virus way back in 1999. He thought he was going to die.

"That rocked my world from then on," he says, "'because when I was growing up hearing about this disease, a lot of people weren't making it."

While Jackson is on his thrice-weekly dialysis treatment, a community health worker comes by to give him his medication. He swallows 10 pills; three of them keep HIV in check.

For most of the past 13 years, however, Jackson hasn't taken his HIV medication every day. "When I was diagnosed with the virus, I was kind of leery about taking the pills," he says. "They kept bothering my stomach. So I kept telling them I'm taking it, but I wasn't."

Eight months ago he got into a program called PACT, or Prevention and Access to Care and Treatment. PACT arranged for a different regimen that doesn't make Jackson sick. A community health worker named Greg Jules makes sure Jackson takes his medicine and otherwise takes care of himself.

"It's been challenging, because Kenya has a long history of the illness. He has a lot of ups and downs," Jules says. "My whole job is to try to make him see I'm in his corner, I'm looking out for him. And whatever we have to do to get there, I'm willing to do."

That means trying to make Jackson's life less chaotic, more predictable. So far, it's working. When Jackson's dialysis session is over, Jules takes him to sign the lease on an apartment. He won't be homeless anymore.

"I'm very happy for you, very excited," Jules tells Jackson. "You're going to have your own place. So therefore, we don't want to do anything to impact that. You want to go into a new way now."

Jackson promises to be "a new Kenya" and stay on his HIV medication this time — to keep himself well, and to avoid infecting anyone else.

In his case, as in many others, it takes a lot of one-on-one attention to turn HIV prevention into HIV treatment. But veterans of the fight against AIDS say it's going to be necessary to break the cycle of infection.

Copyright 2013 NPR. To see more, visit http://www.npr.org/.

Transcript

(SOUNDBITE OF MUSIC)

STEVE INSKEEP, HOST:

It's MORNING EDITION from NPR News. I'm Steve Inskeep.

RENEE MONTAGNE, HOST:

And I'm Renee Montagne. Good morning.

Here's a reason for people with HIV to seek early treatment. Entirely aside from the benefit to their lives, they could be saving the lives of others.

INSKEEP: This month, we're looking at the new era of HIV and AIDS. And today, we'll examine the effects of a change in how - and especially when - HIV is treated.

MONTAGNE: Scientists now believe that getting more people into treatment and starting it sooner could drastically slow the spread of the virus - or even stop it. Some signs indicate that the strategy is already working, as NPR's Richard Knox found in Boston.

RICHARD KNOX, BYLINE: Ben Neely of the Fenway Community Health Center in Boston is about to do an HIV test on a 24-year-old man. He agreed to let us record the session if we didn't use his name.

BEN NEELY: So it's a very tiny needle. Very quick.

(SOUNDBITE OF SNAP)

NEELY: Excellent. So leave your finger there for one second, I'm going to grab a drop of blood out of it.

KNOX: Unlike older HIV tests that took an agonizing two weeks to come back, this test will give a result in 20 minutes.

(SOUNDBITE OF BEEP)

NEELY: So, as you can see, it came back with just one line. That means it's nonreactive for HIV.

KNOX: The test is negative. The man looks relieved. Neely takes some time to do some safe-sex education, and explains that the test won't pick up an infection that occurred within the past six to eight weeks.

NEELY: I would say get tested again at the eighth week mark if there was anything that happened. But I would suggest going forward, getting tested more regularly.

KNOX: Doing more tests for HIV is more important than ever, because it's the only way to catch people soon after they're infected and get them in treatment with antiviral drugs. This is a big change. For a long time in the world of HIV and AIDS, the conventional wisdom has been to delay treatment until people show signs of damage to their immune system.

The drugs have side effects, and few people thought medical treatment itself could slow the spread of HIV. Now, more and more, experts are convinced that treatment is prevention.

Last summer, a big study showed that people with HIV are 96 percent less likely to pass the virus on if they faithfully take antiviral medicine.

KEVIN CRANSTON: After many years of frustration, it is a transformational moment in the course of this epidemic.

KNOX: That's Kevin Cranston of the Massachusetts Department of Public Health.

CRANSTON: Universal treatment can in fact result in an epidemic that looks to be petering out.

KNOX: There's growing evidence it's actually beginning to happen, in Massachusetts and a few other places where the number of people on HIV treatment has reached a tipping point. There are so many people on treatment that new infections are dwindling.

CRANSTON: We, unlike most states and frankly most cities in the country, are seeing a sharp decline in the number of new cases of HIV over the past decade.

KNOX: Cranston says as Massachusetts has expanded antiviral treatment, new infections have fallen by nearly half. Deaths from AIDS are at an all-time low.

CRANSTON: We're approaching a level where the rate of transmission does not sustain an epidemic.

KNOX: But ending the epidemic won't be easy because many people don't know they have HIV or they wait too long to get tested.

Among new cases of HIV in Massachusetts, nearly one in three already has full-blown AIDS or is close to it.

CRANSTON: It's a tragedy if someone doesn't present for care until they have an AIDS diagnosis.

KNOX: Because it means they've been infected for years and able to infect others. It's true all over the country. Nearly a quarter of a million Americans have HIV without knowing it. And many others who do know they're infected are not getting treated. That's why there's a big push now to do what AIDS experts are calling test and treat. Reach out to people who might be infected, get them tested, and if they're HIV-positive, get them into treatment as soon as possible.

DR. ROCHELLE WALENSKY: I don't want the message to be, we can do test and treat and then we're done. 'Cause first, test and treat is not going to be easy. And second, test and treat is not going to be universal.

KNOX: Walensky, at the Massachusetts General Hospital, says the new test and treat programs are never going to get 100 percent of people into effective long-term treatment. But they have to try to get as close as they can.

WALENSKY: If we could find everybody with HIV, link them to care, make sure that they were getting treatment and doing well, we could make a huge dent in this epidemic. Could we eradicate it? Perhaps. Eliminate it? Perhaps. It'll take a long time.

KNOX: The problem is many of those not yet in treatment have other, more urgent priorities than getting tested for HIV and then taking pills for it, without fail, for the rest of their lives.

KNOX: Kenya Jackson is one of those HIV patients who has been very hard to keep in treatment. He's got lots of problems. On top of his HIV infection, Jackson has kidney failure, hepatitis B and high blood pressure. He's also been homeless for years.

Back in 1999, when he found out he had the virus, Jackson thought he was going to die.

JACKSON: That rocked my world from then on 'cause when I was growing up hearing about this disease, a lot of people weren't making it.

KNOX: While he's hooked up to the dialysis machine, a community health worker comes in to give Jackson his medication. He swallows 10 pills - three of them keep HIV in check.

JACKSON: I took the pills because it has to be done, like, at least twice a day every day.

KNOX: But for much of the past 13 years, Jackson hasn't taken his HIV medication every day.

JACKSON: When I was, like, diagnosed with the virus, you know, like, I was kind of like, kind of leery about taking the pills. So, I started, like, laying off them because they kept bothering my stomach. So, I kept telling them I'm taking it, but I wasn't. You know what I'm saying?

KNOX: Eight months ago, he got into a program called PACT, Prevention and Access to Care and Treatment. PACT arranged for a different regimen that doesn't make Jackson sick. A community health worker named Greg Jules makes sure Jackson takes his medicine and otherwise takes care of himself.

GREG JULES: It's been challenging, because Kenya has a long history of the illness. He has a lot of ups and downs. My whole job is to try to make him see, you know, I'm in his corner, I'm looking out for him. And that whatever we have to do to get there, I'm willing to do.

KNOX: Part of Greg Jules's job is making Jackson's life less chaotic, more stable and predictable. And today on that front, there's a breakthrough. Now that Jackson's dialysis session is over, Jules is going to take him to sign the lease on an apartment. He won't be homeless anymore.

JULES: I'm very, very happy for you, very excited. You're going to have your own place. So, therefore, we don't want to do anything to impact that.

JACKSON: That's right.

JULES: That you want to go into a new way now.

KNOX: A new Kenya.

(LAUGHTER)

JACKSON: A new Kenya, yes. Yes indeed, I do.

KNOX: Jules hopes the new Kenya will stay on his medicine this time, not only to keep himself well, but to prevent him from infecting anyone else. In his case, it takes a lot of one-on-one attention to turn HIV treatment into HIV prevention. But veterans of the fight against AIDS say it's going to be necessary to break the cycle of infection. Richard Knox, NPR News, Boston.

INSKEEP: Another way the AIDS epidemic may one day be stopped is by giving drugs that fight HIV to people who are not infected but who are at high risk for getting infected. Several major studies of this strategy are under way around the world, and there are signs of success being reported today in the New England Journal of Medicine.

MONTAGNE: One of the studies, done in Botswana, found a 62 percent lower rate of new infections among people who took an anti-HIV drug versus a placebo. Similar results were found in a study of heterosexual couples in Uganda and Kenya, where one partner is HIV-positive and one is negative.

INSKEEP: So, that's the good news, but getting people to faithfully take their drugs - as we just heard in Richard's piece - can be a challenge. Another study out today done in Kenya, Tanzania and South Africa found no significant reduction in HIV among 2,100 women who were considered at a higher risk for getting the virus. Most of them were not taking their drugs as prescribed.

(SOUNDBITE OF MUSIC)

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